T2 L4: Contraception Flashcards
What are the 3 types of combined hormonal contraceptives (CHC) available to women?
Tablets
Patches
Vaginal rings
What are the types of contraceptive tablets available?
Monophasic: 21 or 28 day pack with a fixed amount of oestrogen and progesterone
Multiphasic: 28 day pack with a variable amount of oestrogen and progesterone
How are contraceptive patches used?
They are worn for a week each for 3 weeks and then a patch free week is done
They release oestrogen and progesterone
How do vaginal rings work?
They are placed inside the vagina and worn for 3 weeks and then removed for a week. A new ring is inserted every 28 days
What are some factors that cause combined hormonal contraceptives (CHC) to fail?
- Weight (90kg or more)
- Malabsorption
- Drug interactions
How much of an CHC is prescribed in one go and why?
A years supply to avoid unwanted discontinuation
What are the benefits of using CHC’s?
- Reduction in ovarian, endometrial, and colorectal cancer risk
- Predictable bleeding patterns
- Reduced dysmenorrhoea and menorrhagia
- Management of symptoms of PCOS
- Acne improvement
- Reduced menopausal symptoms
- Maintaining bone mineral density in women under 50
What are the risks of using CHC’s?
- Increased risk of breast and cervical cancer
- Venous and arterial thromboembolism
How do oral-progestogen-only contraceptives work?
They alter the cervical mucus to prevent sperm penetration and may inhibit ovulation in women
They are used when oestrogens are contra-indicated
How do oral desogestrel-only preparations work?
They constantly inhibit ovulations as their primary mechanism of action
What are some examples of parenteral progestogen-only contraceptives?
Medroxyprogesterone acetate
- A long-lasting progestogen given by injection of prolonged action
- Has a delayed return to fertility and irregular cycles may occur once discontinued but there is no permanent infertility
Noethisterone enantate
- A long-acting progestogen injection that provides 8 weeks of protective
- Used as an interim contraceptive Eg. before a vasectomy becomes effective
Etonogestrel-releasing implant
-A single flexible rid inserted subdermally that lasts 3 years. It’s effects are rapidly reversed upon removal
How does an intra-uterine progestogen-only device work?
Releases levonorgestrel directly into the uterine cavity
Works by preventing endometrial proliferation (thickening of the cervical mucus) and suppression of ovulation in some women
What are the benefits of using a intra-uterine progestogen-only device?
- Return to fertility is rapid upon removal
- Improvements in dysmenorrhoea
- Reduction in blood loss
- Possible reduction in pelvic inflammatory disease
What is pelvic inflammatory disease?
An infection of the upper genital tract, including the womb, ovaries and connecting tubes
What are the 2 forms of emergency contraception?
Levonorgestrel
-Effective if taken 3 days after unprotected sex
Ulipristal acetate
-Effective 5 days after unprotected sex
